clear all
cap log close
do "$data/PSID/parent_identifiers/PID21"

ren *, lower
keep pid2 pid3 pid4 pid5 pid23 pid24

//identifiers
gen uniqid = pid2*1000 + pid3 //generation of uniqid identifier variable
gen uniqid_mother = pid4*1000 + pid5 //generation of uniqid identifier variable
gen uniqid_father = pid23*1000 + pid24 //generation of uniqid identifier variable

keep uniqid*
save "$temp/psid_parent_identifiers", replace